#pragma once
#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define I(x, y, z) ((y) ^ ((x) | (~z)))
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))

#define FF(a, b, c, d, x, s, ac) {\
(a) += F((b), (c), (d)) + (x) + (ac);\
(a) = ROTATE_LEFT((a), (s));\
(a) += (b);\
}
#define GG(a, b, c, d, x, s, ac) {\
(a) += G((b), (c), (d)) + (x) + (ac);\
(a) = ROTATE_LEFT((a), (s));\
(a) += (b); \
}
#define HH(a, b, c, d, x, s, ac) {\
(a) += H((b), (c), (d)) + (x) + (ac);\
(a) = ROTATE_LEFT((a), (s));\
(a) += (b);\
}
#define II(a, b, c, d, x, s, ac) {\
(a) += I((b), (c), (d)) + (x) + (ac);\
(a) = ROTATE_LEFT((a), (s));\
(a) += (b); \
}


static void __md5_cal(BYTE const * x, UINT* state)
{
	UINT a = state[0];
	UINT b = state[1];
	UINT c = state[2];
	UINT d = state[3];
	UINT* block = (UINT*)x;
	FF(a, b, c, d, block[0], 7, 0xd76aa478);/* 1 */
	FF(d, a, b, c, block[1], 12, 0xe8c7b756);/* 2 */
	FF(c, d, a, b, block[2], 17, 0x242070db);/* 3 */
	FF(b, c, d, a, block[3], 22, 0xc1bdceee);/* 4 */
	FF(a, b, c, d, block[4], 7, 0xf57c0faf);/* 5 */
	FF(d, a, b, c, block[5], 12, 0x4787c62a);/* 6 */
	FF(c, d, a, b, block[6], 17, 0xa8304613);/* 7 */
	FF(b, c, d, a, block[7], 22, 0xfd469501);/* 8 */
	FF(a, b, c, d, block[8], 7, 0x698098d8);/* 9 */
	FF(d, a, b, c, block[9], 12, 0x8b44f7af);/* 10 */
	FF(c, d, a, b, block[10], 17, 0xffff5bb1);/* 11 */
	FF(b, c, d, a, block[11], 22, 0x895cd7be);/* 12 */
	FF(a, b, c, d, block[12], 7, 0x6b901122);/* 13 */
	FF(d, a, b, c, block[13], 12, 0xfd987193);/* 14 */
	FF(c, d, a, b, block[14], 17, 0xa679438e);/* 15 */
	FF(b, c, d, a, block[15], 22, 0x49b40821);/* 16 */

	GG(a, b, c, d, block[1], 5, 0xf61e2562);/* 17 */
	GG(d, a, b, c, block[6], 9, 0xc040b340);/* 18 */
	GG(c, d, a, b, block[11], 14, 0x265e5a51);/* 19 */
	GG(b, c, d, a, block[0], 20, 0xe9b6c7aa);/* 20 */
	GG(a, b, c, d, block[5], 5, 0xd62f105d);/* 21 */
	GG(d, a, b, c, block[10], 9, 0x02441453);/* 22 */
	GG(c, d, a, b, block[15], 14, 0xd8a1e681);/* 23 */
	GG(b, c, d, a, block[4], 20, 0xe7d3fbc8);/* 24 */
	GG(a, b, c, d, block[9], 5, 0x21e1cde6);/* 25 */
	GG(d, a, b, c, block[14], 9, 0xc33707d6);/* 26 */
	GG(c, d, a, b, block[3], 14, 0xf4d50d87);/* 27 */
	GG(b, c, d, a, block[8], 20, 0x455a14ed);/* 28 */
	GG(a, b, c, d, block[13], 5, 0xa9e3e905);/* 29 */
	GG(d, a, b, c, block[2], 9, 0xfcefa3f8);/* 30 */
	GG(c, d, a, b, block[7], 14, 0x676f02d9);/* 31 */
	GG(b, c, d, a, block[12], 20, 0x8d2a4c8a);/* 32 */

	HH(a, b, c, d, block[5], 4, 0xfffa3942);/* 33 */
	HH(d, a, b, c, block[8], 11, 0x8771f681);/* 34 */
	HH(c, d, a, b, block[11], 16, 0x6d9d6122);/* 35 */
	HH(b, c, d, a, block[14], 23, 0xfde5380c);/* 36 */
	HH(a, b, c, d, block[1], 4, 0xa4beea44);/* 37 */
	HH(d, a, b, c, block[4], 11, 0x4bdecfa9);/* 38 */
	HH(c, d, a, b, block[7], 16, 0xf6bb4b60);/* 39 */
	HH(b, c, d, a, block[10], 23, 0xbebfbc70);/* 40 */
	HH(a, b, c, d, block[13], 4, 0x289b7ec6);/* 41 */
	HH(d, a, b, c, block[0], 11, 0xeaa127fa);/* 42 */
	HH(c, d, a, b, block[3], 16, 0xd4ef3085);/* 43 */
	HH(b, c, d, a, block[6], 23, 0x04881d05);/* 44 */
	HH(a, b, c, d, block[9], 4, 0xd9d4d039);/* 45 */
	HH(d, a, b, c, block[12], 11, 0xe6db99e5);/* 46 */
	HH(c, d, a, b, block[15], 16, 0x1fa27cf8);/* 47 */
	HH(b, c, d, a, block[2], 23, 0xc4ac5665);/* 48 */

	II(a, b, c, d, block[0], 6, 0xf4292244);/* 49 */
	II(d, a, b, c, block[7], 10, 0x432aff97);/* 50 */
	II(c, d, a, b, block[14], 15, 0xab9423a7);/* 51 */
	II(b, c, d, a, block[5], 21, 0xfc93a039);/* 52 */
	II(a, b, c, d, block[12], 6, 0x655b59c3);/* 53 */
	II(d, a, b, c, block[3], 10, 0x8f0ccc92);/* 54 */
	II(c, d, a, b, block[10], 15, 0xffeff47d);/* 55 */
	II(b, c, d, a, block[1], 21, 0x85845dd1);/* 56 */
	II(a, b, c, d, block[8], 6, 0x6fa87e4f);/* 57 */
	II(d, a, b, c, block[15], 10, 0xfe2ce6e0);/* 58 */
	II(c, d, a, b, block[6], 15, 0xa3014314);/* 59 */
	II(b, c, d, a, block[13], 21, 0x4e0811a1);/* 60 */
	II(a, b, c, d, block[4], 6, 0xf7537e82);/* 61 */
	II(d, a, b, c, block[11], 10, 0xbd3af235);/* 62 */
	II(c, d, a, b, block[2], 15, 0x2ad7d2bb);/* 63 */
	II(b, c, d, a, block[9], 21, 0xeb86d391);/* 64 */

	state[0] += a;
	state[1] += b;
	state[2] += c;
	state[3] += d;
}

static void __md5_update(BYTE const * msg, UINT64 len, UINT64 bit_len, UINT*& state)
{
	UINT64 offset = 0;
	if (len >= 64)
	{
		while (offset + 64 <= len)
		{
			__md5_cal(msg + offset, state);
			offset += 64;
		}
		len -= offset;
	}
	if (len > 56)
	{
		BYTE block[64] = { 0 };
		memcpy(block, msg + offset, len);
		block[len] = 0x80;
		__md5_cal(block, state);
		memset(block, 0, 56);
		memcpy(block + 56, &bit_len, 8);
		__md5_cal(block, state);
	}
	else if (len == 56)
	{
		BYTE block[64] = { 0 };
		memcpy(block, msg + offset, len);
		memcpy(block + 56, &bit_len, 8);
		__md5_cal(block, state);
	}
	else if (len > 0)
	{
		BYTE block[64] = { 0 };
		memcpy(block, msg + offset, len);
		block[len] = 0x80;
		memcpy(block + 56, &bit_len, 8);
		__md5_cal(block, state);
	}
	else
	{
		BYTE block[64] = { 0x80 };
		memcpy(block + 56, &bit_len, 8);
		__md5_cal(block, state);
	}
}


static void MD5(BYTE const * in, UINT64 in_len, BYTE* out)
{
	UINT* state = (UINT*)out;
	state[0] = 0x67452301;
	state[1] = 0xefcdab89;
	state[2] = 0x98badcfe;
	state[3] = 0x10325476;
	__md5_update(in, in_len, in_len << 3, state);
}